Claim: CO2 ended the last ice age

From Oregon State University

Study explains early warming of West Antarctica at end of last ice age

CORVALLIS, Ore. – West Antarctica began emerging from the last ice age about 22,000 years ago – well before other regions of Antarctica and the rest of the world, according to a team of scientists who analyzed a two-mile-long ice core, one of the deepest ever drilled in Antarctica.

Scientists say that changes in the amount of solar energy triggered the warming of West Antarctica and the subsequent release of carbon dioxide (CO2) from the Southern Ocean amplified the effect and resulted in warming on a global scale, eventually ending the ice age.

Results of the study were published this week in the journal Nature. The authors are all members of the West Antarctic Ice Sheet Divide project, which was funded by the National Science Foundation.

The study is significant because it adds to the growing body of scientific understanding about how the Earth emerges from an ice age. Edward Brook, an Oregon State University paleoclimatologist and co-author on the Nature study, said the key to this new discovery about West Antarctica resulted from analysis of the 3,405-meter ice core.

“This ice core is special because it came from a place in West Antarctica where the snowfall is very high and left an average of 20 inches of ice or more per year to study,” said Brook, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Not only did it allow us to provide more accurate dating because we can count the layers, it gave us a ton more data – and those data clearly show an earlier warming of the region than was previously thought.”

Previous studies have pointed to changes in the Earth’s orbit around the sun as the initial trigger in deglaciation during the last ice age. An increase in the intensity of summer sunlight in the northern hemisphere melted ice sheets in Canada and Europe starting at about 20,000 years ago and is believed to have triggered warming elsewhere on the globe.

It previously was thought that Antarctica started its major warming a few thousand years later, at about 18,000 years before present. However, the new study shows that at least part of Antarctica started to warm 2,000 to 4,000 years before this. The authors hypothesize that changes in the total amount of sunlight in Antarctica and melt-back of sea ice caused early warming at this coastal site – warming that is not recorded by ice cores in the interior of the continent.

“The site of the core is near the coast and it conceivably feels the coastal influence much more so than the inland sites where most of the high-elevation East Antarctic cores have been drilled,” Brook said. “As the sunlight increased, it reduced the amount of sea ice in the Southern Ocean and warmed West Antarctica. The subsequent rise of CO2 then escalated the process on a global scale.”

“What is new here is our observation that West Antarctica did not wait for a cue from the Northern Hemisphere before it began warming,” Brook said, “What hasn’t changed is that the initial warming and melting of the ice sheets triggered the release of CO2 from the oceans, which accelerated the demise of the ice age.”

Brook said the recent increase in CO2 via human causes is also warming the planet, “but much more rapidly.”

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Latitude

and the subsequent release of carbon dioxide (CO2) from the Southern Ocean amplified the effect
Do they say what CO2 levels were at the start?…..and what they increased to?

Watermelon

Speculation..

dp

Scientists say that changes in the amount of solar energy triggered the warming of West Antarctica and the subsequent release of carbon dioxide (CO2) from the Southern Ocean amplified the effect and resulted in warming on a global scale, eventually ending the ice age.

So it was increased insolation, not CO2 that was the trigger. CO2 retained some of the heat in the atmosphere as one would expect, but it was old man Sol that was the source of the heat being retained. The CO2 came from the oceans that Sol warmed if this analysis is to be believed. I don’t yet see the tie-in to West Antarctica, but a jutland is very prone to the local oceanic climate, so if in fact the sun warmed the oceans it may have created a melt of the WA jutland.
One presumes the CO2 level over time is charted somewhere at the OSU site but until it shows up I’ll just have to take their word for it, or not.
Not reaching for my checkbook to fund more of this quite yet.

Peter Miller

Here’s the scary conclusion, never mind that it is obvious BS, just gimme some more grants to study this phenomenon further.
Double the money for the next 5 years might just be enough to better understand this.

The CO2 claim is baseless.
The significance of this core is that it agrees with the Taylor Dome cores that show simultaneous Arctic and Antarctic warming at the start of this interglacial.
Why other Antarctic cores show lagged Antarctic warming is a bit of a mystery.
http://depts.washington.edu/isolab/taylor/

Its just amazing that CO2 is worked into everything, almost as if it would impact their funding, I came across this BBC documentary on The Sunspot Mystery from 35yrs? ago, before they went CO2 crazy. http://www.youtube.com/watch?v=vZVsoSvDmm0

Ivan

“Brook said the recent increase in CO2 via human causes is also warming the planet, “but much more rapidly.”’
So the temperature is now increasing faster than at the end of last Ice Age, when it increased 7 or 8 degrees globally???

Hot under the collar

So to confirm, global warming due to natural “CO2” release ended the last ice age 22,000 years ago with no human causation, but recent increase in CO2 is mostly “human caused” and warming the planet “much more rapidly”?
And everytime we don’t believe this a fairy dies?

Tex

So the sun caused the CO2 levels to rise because the oceans warmed up…but it was the CO2 that brought us out of the ice age? Huh? Wouldn’t that mean it was the sun that brought us out of the ice age and the CO2 was just along for the ride, since the oceans were already warming before CO2 started to rise? Somebody seems to have their cause and effect relationships confused.

Did they consider that whatever caused the initial melting, just continued and CO2 is irrelevant?
thanks
JK

1sky1

What is truly consistent about this study is the reliance upon the CO2 mantra to obtain funding.
sky

Bryan A

Scientists say that changes in the amount of solar energy triggered the warming of West Antarctica and the subsequent release of carbon dioxide (CO2) from the Southern Ocean amplified the effect and resulted in warming on a global scale, eventually ending the ice age.
Sounds to me like a case of CO2 lagging Temperature

Mark Bofill

All this really amounts to is a claim that the ~something~ that amplifies solar influence is CO2. Well, fine, but have you guys actually ~looked~ for any other amplification mechanisms? Even taking as a given that Svensmark is wrong about cosmic rays, the reaction to his ideas implies that the answer to my question is an emphatic ‘heck no!’

Janice Moore

Sounds exactly like it, Bryan A. (2:38PM)
*****************************
Book of Climastrology (Rev. Ed.)
“… the recent increase in CO2 via human causes is also warming the planet, ‘but much more rapidly.’” Thus, saith the Brook.

Tom J

To fully explain and appreciate the results obtained from this study requires the insertion of a few words added to the heading and the initial paragraph. So allow me to copy the aforementioned heading and paragraph, and then my clarified version immediately following:
‘Study explains early warming of West Antarctica at end of last ice age
CORVALLIS, Ore. – West Antarctica began emerging from the last ice age about 22,000 years ago – well before other regions of Antarctica and the rest of the world, according to a team of scientists who analyzed a two-mile-long ice core, one of the deepest ever drilled in Antarctica.’
Now for my clarified version:
Government funded study explains (probably to its funding source’s expectation) early warming of West Antarctica at end of last ice age
CORVALLIS, Ore. (and probably Washington, DC) – West Antarctica began emerging from the last ice age about 22,000 years ago – well before other regions of Antarctica and the rest of the world, according to a government funded team of government funded scientists who analyzed a government funded two-mile-long ice core, one of the deepest (and probably most expensive) ever drilled through a government funded research station in Antarctica.
See how easy it is to understand this research? Ok, let’s not dignify this by calling it research. But you get the idea.

Eliza

We may be observing the first effects of enlargement of antarctica on reach of cold air masses into tropics!
http://wxmaps.org/pix/sa.00hr.html
Probably nonsense if you check back to previous years LOL

Jimbo

Brook said the recent increase in CO2 via human causes is also warming the planet, “but much more rapidly.”

That’s why global warming has stalled for the last 16 or more years.
Skeptical Science says that the Ordovician glaciation was triggered when co2 fell from 5,600 ppm to below 3,000ppm. They blame low solar output. I say let’s keep the Sun out of this debate eh.

Wikipedia says the main objective of the West Antarctic Ice Sheet Divide project is to produce an accurate CO2 record.
Yet, curiously there is no mention of any CO2 related data in the press release.

William Sears

How can there be a west Antarctica? Since it covers the South Pole, what reference line would be unambiguous. 🙂

stuart T

Utter BS and one ice core doesn’t proove anything. The Sun and Cosmic Rays, enough said.

Robert Parker

Aren’t we still in an ice age? Thought an ice age was just any period that had ice at the poles, and we’re in the interglacial time period. Unless I have the wrong definition that’s pretty sad to get wrong in a nature journal

(quoting article) “What hasn’t changed is that the initial warming and melting of the ice sheets triggered the release of CO2 from the oceans, which accelerated the demise of the ice age.”
Well tra de dah, …. the initial warming and melting of the coastal ice triggers a horror’endous release of warm H2O vapor into the near surface atmosphere, where it will absorb 2X the solar energy than any CO2 molecules will, and then that Warm Front’ed air mass will move inland and the glacial ice will begin to melt like an icecube on hot blacktop.
That same/similar process occurs every Springtime all across the Northern tier of North America.
Been there, lived there, seen it happen every Spring. And as far as I know it is still repeating that yearly cycle.
And ps, that initial warming and melting would not have triggered the release of any more CO2 from the ocean than does the Antarctica springtime warming does now days. Henry’s Law determines the ingassing/outgassing of CO2, …. the melting of glacial ice doesn”t.

Ian W

Nitrogen and Oxygen are non-radiative gases – warm them up and they stay warm and do not radiate infrared. Add some CO2 and the CO2 warmed by collision – radiates infrared cooling the Nitrogen Oxygen mixture. For some reason this tropospheric cooling effect is disregarded (although it is discussed as cooling the stratosphere). CO2 radiating atmospheric heat does not appear in any of the AGW Mickey Mouse diagrams which only consider the absorption of surface radiation. It is probable that the CO2 radiative cooling effect may be equal or greater than heating by the absorption of infrared from the surface.
Has anyone actually done any experiments in this area?

Chris @NJSnowFan

Good point Tex
The sun is in a weak phase now and for how long no one knows. S Hem Uses ice around Antarctic has been increasing more and more every year. So what they said is sea ice decreased and oceans warmed. Exact opposite then what is happening today.
Hypothesis of their study is keep the Government funds and grant $$ flowing

AlecM

There is no significant CO2-GW. The real explanation is the reduction of cloud albedo by biofeedback. More later…..:o)

David Ball
Txomin

As presented, it seems the release of CO2 was a by-product, not a cause, of warming.

Scientists say that changes in the amount of solar energy triggered the warming of West Antarctica and the subsequent release of carbon dioxide (CO2) from the Southern Ocean
=====================
So the sun was the cause, and CO2 the effect.
And why is the warming since the LIA not the cause of the release of CO2 today? How is it that warming in the past released CO2, but now warming doesn’t release CO2. Instead if must be humans.
Same excuse doctors use when they can’t find the cause of a disease – it must be something the patient is doing that is causing the problem.

Ian W says:
August 14, 2013 at 3:25 pm
Add some CO2 and the CO2 warmed by collision – radiates infrared cooling the Nitrogen Oxygen mixture.
============
this is why the atmosphere cools with altitude. otherwise it would be isothermal.

JimS

The last glaciation period ended because the earth’s eccentricity was at its peak, as was its obliquity, and the precession of the earth made it receive the maximum solar input to the northern hemisphere in the summer. The periods of glaciation and their end have little to do with what happens in the southern hemisphere, but rather, everything to do with what happens north of the equator. I can not believe these people call themselves scientists.

ferd berple says:
August 14, 2013 at 4:04 pm
this is why the atmosphere cools with altitude. otherwise it would be isothermal
================
this process would continue except that vertical circulation kicks in to limit the drop in temperature to the lapse rate – which is governed by gravity. objects can only fall so fast, so the conversion of PE to KE and thus temp/altitude is bound to gravity, moderated by the phase change of water.

Richard

This headline says differently:
“Earth Orbit Changes Key to Antarctic Warming That Ended Last Ice Age”
“the warming in West Antarctica 20,000 years ago is not explained by a change in the sun’s intensity. Instead, how the sun’s energy was distributed over the region was a much bigger factor. It not only warmed the ice sheet but also warmed the Southern Ocean that surrounds Antarctica, particularly during summer months when more sea ice melting could take place.”
Twas the Sun and then the CO2
http://www.sciencedaily.com/releases/2013/08/130814132228.htm

Pamela Gray

No, it was not the Sun. The Earth’s axil wriggle in its orbit around the Sun caused the initial warming. And when it wriggles back the Earth’s tilt will bring about cooling. The Sun didn’t do anything but sit there and beam.

Pedantic old Fart

So earlier warming of west Antarctica triggered loss of sea ice there and this became general regional warming that degassed CO2 from the southern ocean and terminated the most recent ice age?` Still seems cold down there…..lots of ice all over the place (over 3000m of it where they drilled). Do we have another end of the ice age each time the major oceans’ decadal oscillations turn over, diminishing west Antarctic sea ice?

Bill H

This reads like a dang Monty Python script..
“Bring out the Holy Hang Grenade” Thous shall count to three, not four, and certainly not five”

Rob R

Jim S
As a scientist with substantial knowledge of this topic I would be surprised if the mechanisms causing glacial terminations are as simple as you seem to imply. The global climate system is fairly (an understatement) complex, hence the reason why it has been so difficult to model. You should refrain from making such inane evidence-free statements as you are revealing the depth of your ignorance.

Richard

“No, it was not the Sun. The Earth’s axil wriggle in its orbit around the Sun caused the initial warming. And when it wriggles back the Earth’s tilt will bring about cooling. The Sun didn’t do anything but sit there and beam.”
It was changes in the the Sun’s insolation. Sun sun sun.

Max

“Scientists say that changes in the amount of solar energy triggered the warming of West Antarctica and the subsequent release of carbon dioxide”
My “take aways”: 1) It’s the sun and 2) CO2 *follows* temperature.

JaneHM

The Milankovitch trigger for the end of the last glacial period is increased insolation at mid-latitudes in the NORTHERN hemisphere

Richard M

Let’s see … the sun causes some melting over the NH glaciers. The glaciers retreat. The albedo is reduced causing more warming. Repeat. The glaciers eventually disappear. No CO2 required.

JimS

@Rob R
Rob R wrote: “As a scientist with substantial knowledge of this topic I would be surprised if the mechanisms causing glacial terminations are as simple as you seem to imply. The global climate system is fairly (an understatement) complex, hence the reason why it has been so difficult to model. You should refrain from making such inane evidence-free statements as you are revealing the depth of your ignorance.”
Jim S writes: My explanation is a far better one than suggesting that CO2 had any effect whatsoever in ending the last glaciation period or any of the other glaciation periods over the last 2.6 million years. Given the data record we have of CO2 concentrations, and the claim by AGW extremists that atmospheric CO2 has not risen above 280 ppm for the last 400,000, any claim that this amount of CO2 is significant enough to end a period of glaciation is ludicrous at best. Their own cockeyed theories stand against them.
If you want evidence as to what the conditions were 12,000 year ago regarding the Milankovitch cycles, and since you claim to be a scientist, then you should know that what I described was exactly where those cycles were. As to what the actual trigger(s) are that start or stop periods of glaciation, is still a mystery, granted. However, if one wants to even imagine that CO2 has much to do with abrupt climate temperature changes, in my opinion, they should be stripped of holding the honour of being called a “scientist.”

Eliza says:
August 14, 2013 at 2:58 pm
We may be observing the first effects of enlargement of antarctica on reach of cold air masses into tropics!
http://wxmaps.org/pix/sa.00hr.html
Probably nonsense if you check back to previous years LOL
Reply; This cold air invasion is the direct result of the lunar declinational tidal effects in the atmosphere, moon will be at maximum culmination South extent on the 16th. This atmospheric surge in cold air mass will peak one or two days later, happens every SH winter.

TalentKeyHole Mole

Hello,
Any One ice core is as useless as any One NOAA near-surface mercury thermometer.

Don Easterbrook

Apparently these folks can’t read the literature or they would realize that every study of the timing of warming vs CO2 in Antarctica shows that CO2 FOLLOWS warming, not the other way around. (for a good summary of these studies, see Jo Nova’s website). So how can CO2 be responsible for the warming if the warming came first? Even with modern warming, CO2 lags warming.

Bill Illis

From 22,900 years ago to 17,500 years ago …
… CO2 increased from 189 ppm to 188 ppm.
Climate science math.

Chad Wozniak

No science here . . . just a bunch of cats dancing around on a hot tin roof. Problem is, all their acrobatics only dig them in deeper.
A parallel piece of ignorance on the CBS Evening Propaganda tonight: Bob Schieffer says that California redwoods are growing faster than ever because of climate change, which is making the growing season longer.
Problem #1: “Growing season” doesn’t have much relevance in the climate of the Redwood Empire. It’s cool and damp the year round, frost is rare. In many areas you can go a whole year staying between 40 F and 55 F and have that same spread in any month of the year.
Problem #2: In general, growing seasons, where they are relevant, are getting shorter (corn belt planting a month late, in May, and threats of first frost later this month – yes, that’s August we’re talking about.) The same in Europe and Australia. Definitely not longer.
Problem #3: More rapid growth of redwoods would be expected, as for any other plant life, as the result of increased CO2 in the atmosphere and the resultant effects of fertilization and moisture retention.
Pardon me if I see a bit of a difficulty in Schieffer’s pontification.

Janice Moore

Nice insight, Chad Wozniak. Basically, Schieffer lied, er, pardon me. READ a lie.
“CBS Evening Propaganda” — LOL.
Any book news? Composing/playing news? Has #23 come and gone? Hope it was happy.

Gail Combs

Ivan says: @ August 14, 2013 at 2:30 pm
“Brook said the recent increase in CO2 via human causes is also warming the planet, “but much more rapidly.”’
So the temperature is now increasing faster than at the end of last Ice Age, when it increased 7 or 8 degrees globally???
>>>>>>>>>>>>>>>>>>>>>>>>
Yeah, “Richard Alley, one of the world’s leading climate researchers and his colleagues found that the last ice age came to an abrupt end over a period of only three years and found local warmings as large as 16°C, occurred repeatedly during the slide into and climb out of the last ice age. “
http://www.amazon.com/Two-Mile-Time-Machine-Abrupt-Climate/dp/0691102961
Also SEE: “Abrupt Climate Change – Inevitable Surprises”, Committee on Abrupt Climate Change, National Research Council of the National Academy of Sciences, 2002, Dr. Alley Chair
http://www.nap.edu/openbook.php?isbn=0309074347
Some how I do not think we are seeing human caused warming of the planet, as high as 16°C.
Even Hansen, Mann and Jones together can’t manage that.

F. Ross

Did the author(s?) give any consideration to the possibility of geothermal activity in W. Antarctica?
Probably not; after all, what else could it be but CO2?